Endless recursion when handling responses from an IAS-ECC card in iasecc_select_file in libopensc/card-iasecc.c in OpenSC before 0.19.0-rc1 could be used by attackers able to supply crafted smartcards to hang or crash the opensc library using programs.
https://www.x41-dsec.de/lab/advisories/x41-2018-002-OpenSC/
https://lists.debian.org/debian-lts-announce/2019/09/msg00009.html